High-speed data printout

ABSTRACT

Signals identifying alphanumeric characters for a plurality of lines of printing are temporarily stored in a memory while recording paper moves through a printing station having a plurality of rows of character-imprinting elements. Each row is comprised of identical character-imprinting elements and the number of rows is at least equal to the number of distinct characters which may be printed. A control system repetitively examines the memory to detect momentary coincidences between positions on the moving paper and any imprinting elements of any row which correspond to a character to be imprinted at those positions. The control system activates the appropriate imprinting elements as such coincidences occur to effect a very fast multiline form of printout. The rows of imprinting elements are defined on a flat stationary unitized member which may readily be removed and replaced and in which individual rows may be replaced as a unit and the associated actuating elements are also unitized for rapid replacement. Line spacing is adjustable and the system is adaptable to the printing of graphical or pictorial data.

United States Patent Inventor Carl F. Hodel Berkeley, Calif.

App]. No. 753,114

Filed Aug. 16, 1968 Patented Sept. 28, 1971 Assignee DHM Research 8:Development Corporation San Francisco, Calif.

HIGH-SPEED DATA PRINTOUT 25 Claims, 15 Drawing Figs.

U.S. Cl 178/25, 101/4012, 346/74 ES Int. Cl .1104] 17/30, GOld 15/16Field of Search 178/25, 36; 346/74 ES, 74 MP References Cited UNITEDSTATES PATENTS Primary Examiner-Kathleen H. Claffy AssistantExaminer-Thomas W. Brown Attorney-Fryer, Tjensvold, Feix, Phillips &Lempio ABSTRACT: Signals identifying alphanumeric characters for aplurality of lines of printing are temporarily stored in a memory whilerecording paper moves through a printing station having a plurality ofrows of character-imprinting elements. Each row is comprised ofidentical character-imprinting elements and the number of rows is atleast equal to the number of distinct characters which may be printed. Acontrol system repetitively examines the memory to detect momentarycoincidences between positions on the moving paper and any imprintingelements of any row which correspond to a character to be imprinted atthose positions. The control system activates the appropriate imprintingelements as such coincidences occur to effect a very fast multiline formof printout. The rows of imprinting elements are defined on a flatstationary unitized member which may readily be removed and replaced andin which individual rows may be replaced as a unit and the associatedactuating elements are also unitized for rapid replacement. Line spacingis adjustable and the system is adaptable to the printing of graphicalor pictorial 3,348,232 10/1967 King 346/74ES atar37 SPEED CONTROL 44(I23 1' LINE 233 SIGNAL 39 y GENERATOR o 52 I26 I 1 his is 22 32 |Z9 lf) 38 29 5 6 33 2 if 3 a i as a n4 us i ,122 ,lzi SOLENOID PRINT DATACOMPUTER DRIVERS LOGIC "'sromxss PATENTED SEP2 8 12m SHEET 01 0F 10 mjii NM mObQmmZmw 44205 m2:

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ATTORNEYS HIGH-SPEED DATA PRINTOUT BACKGROUND OF THE INVENTION Thisinvention relates to the printing of information from coded inputsignals and more particularly to apparatus for efficiently realizingvery high speeds in the printout of information from electronic dataprocessing systems.

Many conventional printing operations are essentially duplicative incharacter in that the basic object is to reproduce one or more copies ofinformation which already exist in the alphanumeric form identical to orclosely resembling the printed information. These duplicative printingoperations are typified by traditional printing at a press to reproducea written manuscript and by photostating and electrostatic copying orthe like. Recent advances in computer technology have given emphasis toa second somewhat distinct category of printing operation in which theinformation to be printed does not initially exist in anythingresembling the printed form but is represented instead by coded signalsof the type which may be stored in a memory circuit or device. Aprinting system of this type must translate the coded signals into theappropriate alphabetical or numerical characters as it prints.

The printout of information which is generated within a digital computerobviously requires translative printing techniques. In addition, suchtechniques are now being used for printing operations which havetraditionally been duplicative in character. For example, manycommercial organizations have adopted computer processing as a means forcomputing, printing and addressing monthly bills. Some libraries,notably those of the technical variety, have ceased storing printedcopies of documents and are utilizing magnetic tape or the like topreserve information. This requires translative printout when access tothe information is desired. There are many other commercial andscientific operations which require the printout of imprint which isinitially in coded signal form and the practice of these operations isincreasing at an extremely rapid rate.

In these systems, printout speed has become a critical consideration.Just as the human hand cannot write as fast as the mind can think,commercially available printers cannot operate ata rate comparable tothe speed at which most dataprocessing systems deliver information inthe form of electrical pulses or the like. It is widely recognized thatthe overall efficiency of computer systems is badly limited by therelatively slow speeds of the available printout mechanisms.

While there are several basic types of printout mechanism, each hascharacteristics which prevent the printing of information in anefficient and reliable manner at the speeds which are theoreticallydesirable. Unfortunately, those types of printer which operate at thefaster speeds are in general those which require complex apparatus,expensive recording paper, or produce characters with relatively poorlegibility or permanence.

Electrical typewriter printers, for example, provide good legality anddurability and use inexpensive paper however printing speed is extremelypoor as each letter of each line must be imprinted in sequence. Toprovide faster output, many data processing operations use an on-the-flyprinter of the kind in which rows of character imprinting elements areprovided on a revolving drum. This is still undesirably slow as eachline of the recording paper must be kept at periphery linear-printingzone for a time period sufficient to sweep all rows of imprintingcharacters on the drum past the line on the paper. Somewhat higherspeeds are realized with another class of printout device which utilizesa cathode-ray tube or the like to display lines of characters forimprinting upon photographically sensitive paper. Such paper isrelatively expensive, the necessary developing components may be complexand there are still limitations to printout speed in the form ofelectronic complications at the cathode-ray tube, required exposuretimes at each line and other factors.

To resolve the printing speed limitations of conventional equipment, ithas heretofore been proposed to make use of a multiline parallelprinting technique in which the printing mechanism works on portions ofmany successive lines of printing at the same time. In particular, ithas been proposed that the paper be moved past a printing stationcomprised of many rows of character-imprinting elements with each rowbeing composed of like character-imprinting elements and with a numberof rows equal to the number of distinct characters which are to beimprinted. Each time that the paper advances one line space,character-imprinting elements which are juxtaposed at that moment with aposition on the paper requiring the corresponding character are actuatedsimultaneously. Any given line of printing is built up gradually as itpasses along the series of rows of imprinting elements. This offers theprospect of strikingly greater printing speeds than can be realized byprinters which must complete an entire line or a group of whole linesbefore the paper can be advanced a significant amount.

While the speed advantage of the multiline parallel form of printing isevident, the technique has not heretofore been practiced in the art toany great extent. The difficulty involved can be understood consideringthe fact that a mechanism of this kind designed to print the standardcharacter lines and having a full set of alphanumeric characterssupplemented by punctuation marks and the like requires about 65 rows ofcharacter imprinting elements. Thus over 7,000 separate characterimprinting components are needed together with a matching number ofactuators. In prior proposed constructions, the many character definingelements must each be carried on movable mechanism and, together withtheir associated actuators, must be physically packed into a constrictedspaced dictated by the acceptable character size, character spacing andline spacing. Understandably, the constructions heretofore proposed hasbeen extremely complex from the mechanical standpoint and are vulnerableto excessive downtime and maintenance difficulty. Further, these priorconstructions are characterized by inherent operational inflexibilitieswith respect to such factors as line spacing, character size andinterchangeability of type font.

SUMMARY OF THE INVENTION The present invention provides a simplified,reliable and operationally flexible multiline parallel printing systemcapable of printout speeds substantially higher than those realized withcommonly used conventional techniques.

The invention utilized a memory to store temporarily the input signalsrepresentative of characters for a plurality of lines of printing.Recording paper or the like is moved continuously past an array ofstationary character defining elements arranged in a plurality of rowsand preferably carried on a single unitized replaceable member. Thearray of imprinting elements is associated with a matching array ofactuating means which variously may be electromechanical, electrostaticor other. As the paper moves, a control circuit repetitively inspectsthe memory to detect momentary coincidences between areas of the paperand imprinting elements corresponding to characters to be printed atsuch areas. Upon detection of such coincidences, the control systemenergizes the appropriate actuating elements. Normally, this results ina gradual, seemingly random completion of each line of printing as theline on the paper travels past the successive rows of imprintingelements as portions of a large number of successive lines are beingimprinted more or less concurrently.

The present invention differs from prior parallel printers in that themultiplicity of characterdefining elements are stationary and arepreferably all disposed at a single flat fixed surface along which thepaper travels. Any specifie imprinting element is energizableindependently of the timing of energizing of the imprinting elements ofother rows whereby the spacing of lines of printing on the paper is notinherently fixed by the spacing of the rows of imprinting elements butmay be varied by adjusting a control.

Because the character-defining elements are fixed, the elements may allbe located on a single member which may be removed and replaced as aunit to interchange type face with a minimum of delay or difficulty.Further, in a preferred form, individual rows of character-definingelement are also removable as a subunit for quick and convenientreplacement. Similarly, the associated actuator elements may readily beremoved and replaced in unitized groups to minimize downtime fromcomponent malfunction. The invention further provides practicalarrangements for the disposition of the large number of actuators whichmay be solenoid-controlled hammers for example, at the printingmechanism without introducing undesirable constraints to the size orspacing of characters. The invention rovides still other features to behereinafter described which jointly contribute to the efficient andreliable application of the multiline parallelprinting technique tocomputer printout and related printing operations.

Accordingly, it is an object of this invention to provide for higherprinting speeds from coded signal input data than has heretofore beencustomarily realized.

It is a further object of the invention to provide for greaterflexibility in a multiline parallel-printing system with respect to typefont, line spacing and size and spacing of characters to be printed.

It is another object of the invention to provide a multilineparallel-printing system in which printing speed is not limited by theoperation time of individual character-imprinting means and theactuating means therefor.

It is still another object of the invention to provide for a compact,unitized and simplified construction for a multiline parallel printoutapparatus in which the interchanging and replacement ofcharacter-defining elements as well as the actuating elements thereforis greatly simplified and facilitated.

The invention, together with further objects and advantages thereof,will best be understood by reference to the following specificationtaken in conjunction with the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS In the accompanying drawings:

FIG. 1 is a partially diagrammatic, perspective view of a firstmechanism for printing from coded signals wherein electromechanicallyactuated elements are utilized to perform the imprinting operation;

FIG. 2 is an elevation section view take along line 2-2 of FIG. 1illustrating certain of the internal elements of the printing structurethereof;

FIG. 3 is a foreshortened view taken along the plane indicated by line3--3 of FIG. 2 illustrating the face of a matrix of character-definingelements which is a component of the mechanism of FIG. 1;

FIG. 4 is an elevation section view along a portion of the plane definedby line 4-4 of FIG. 2 further illustrating the internal construction ofthe mechanism of FIG. 1;

FIG. 5 is a broken out view of one end of a row assembly of solenoidsand hammers which constitute the imprinting element-actuating means inthe mechanism of FIG. 1 and illustrating one structure for accommodatingthe necessary number of solenoids in a constricted space;

FIG. 6 is a first section view of the assembly of FIG. 5 taken alongline 6-6 thereof;

FIG. 7 is a second section view of the assembly of FIG. 5 taken alongline 7-7 thereof;

FIG. 8 is a section view taken along line 8-8 of FIG. 5 furtherillustrating the electrical connector and hammer construction;

FIG. 9 is a fragmentary section view illustrating alternate arrangementsfor mounting character-defining elements in the printing apparatus ofFIGS. 1 to 8;

FIG. 10 is a diagrammatic view illustrating a modified arrangement ofcharacter-defining elements and actuating solenoids for a printeressentially similar to that of FIGS. 1 to 8;

FIG. 11 is a diagrammatic view of still another modification of theprinting mechanism of FIGS. 1 to 8 whereby operation at still higherspeeds may be realized;

FIG. 12 is a diagrammatic view of a modification of the printingapparatus of FIGS. 1 to 8 with which graphical and pictorial printingmay be performed thereby;

FIG. 13 is a partially diagrammatic perspective view of a secondprinting mechanism in accordance with the invention wherein imprintingis accomplished by electrostatic means;

FIG. 14 is a foreshortened fragmentary section view taken along theplane columns by line 14-14 of FIG. 13 and illustrating a matrix ofcharacter-imprinting elements utilized in the electrostatic printer; and

FIG. 15 is a cross section view of portions of the electrostaticprinting mechanism taken along line 15-15 of FIG. 14 and illustratinginternal elements of the apparatus.

DESCRIPTION OF THE PREFERRED EMBODIMENTS The invention is adaptable tousage in a variety of data processing contexts which are related insofaras information to be printed out on a recording medium in alphabeticalor numerical form is represented initially by coded signals which areusually binary-coded electrical pulses. Referring now to FIG. 1 of thedrawing, a typical source of such signals is a digital computer 21. Thesignals which are to be decoded and printed may be generated by thecomputer 21 itself or may be data derived essentially from externalsources and which has been processed and transmitted through thecomputer. In other instances, the source of signals may not be acomputer but may merely be an input component of the type which readsthe signals from a magnetic tape or other data storage device. Ashereinbefore discussed, it is characteristic of most such signal sourcesthat data is generated or delivered at a rate exceeding that at which itcan be printed out by conventional printing mechanisms.

In the embodiment of FIG. 1, imprinting of the characters on a recordingweb such as paper 22 or the like is performed by electromechanical meansat a printing station 23. The mechanism includes a flat rectangularactuator housing 24 secured to the top surface of a suitable supportframe 26 by bolts 27 and a flat rectangular-type matrix housing 28secured to housing 24 by bolts 29. The housings 24 and 28 are separateda small distance by spacer elements 31 therebetween to provide a thinpassage 32 through which the paper travels.

The paper 22 is carried through the printing station 23 by a drivesystem which may be of essentially conventional construction exceptinsofar as high paper speeds are provided for. Accordingly, thepaper-driving means is shown schematically in FIG. 1 as a series ofpaired parallel drive rollers 33 situated at both the input and outputends of the printing station with the paper 22 being passed between eachpair of rollers. One or more pairs of the rollers 33 are turned by asuitable electrical motor 34 through the first speed reduction mechanism35 to travel the paper through the printing station 23 in the directionindicated by arrows 36. To accommodate to different printing operationsand different operating conditions it is desirable that the paper drivemotor 34 be of the variable speed type and that it be provided with aspeed control 37 which may be adjusted by an operator.

To provide for the imprinting of characters on the paper 22 as willhereinafter be described in more detail, an inked ribbon 38 travelsthrough the printing station passage 32 immediately above the paper andbelow the type matrix housing 28. Ribbon 38, which is about as wide asthe paper 22, extends from a supply reel 39 above the input end of theprinting station 23 to a takeup spool 41 at the output end, the ribbonbeing passed under a guide roller 40 at each end of the printingstation. It is advantageous to drive the ribbon 38 by the same meanswhich drives the paper 22 inasmuch as any change of paper speed maythereby be matched by an appropriate change of ribbon speed. However itis unnecessary that the ribbon travel as fast as the paper andaccordingly the ribbon may be driven by coupling the takeup spool 41 tothe output of a second speedreducing mechanism 42 which is driventhrough the first speed-reducing mechanism 35.

Considering now an important aspect of the invention which provides forstructural simplicity and operational flexibility, the type matrixhousing 28 contains a flat rectangular type matrix member 43 whichcarries all of the multiplicity of character-defining elements requiredfor multiline parallel printing. Type matrix member 43 is readilyremovable and replaceable as a unit as will hereinafter be described inmore detail.

Referring now to FIGS. 2 and 3 in conjunction, the type matrix member 43has a recess around the lower edges thereof defining a surface 44 whichrests upon an inwardly directed shelf 46 of housing 28 whereby thematrix member is supported with the lower surface 47 thereof at thepassage 32 through which the paper 22 and ribbon 38 is passed. Matrixmember 43 is held within the housing 28 by a flat top door 48 having oneend fastened to an end of the housing by suitable hinges 49. As shown inFIG. 1, door 48 has a handle 51 opposite from the hinges whereby it maybe swung upwardly to provide for removal of the matrix member 43. Tofacilitate this operation, additional handles 52 are provided at the topsurface of the matrix member 43 and the door 48 has openings 53 to avoidinterference therewith. As shown in FIG. 2 in particular, a lining 54 ofresilient material such as rubber is preferably disposed on theunderside of door 48 to aid in holding the matrix member 43 in position.A latch 58, shown in FIG. I, holds the door closed.

Referring again to FIGS. 2 and 3 in conjunction, matrix member 43carries parallel rows of character-defining elements 59 which in thepresent example include a complete set of arabic alphabetical andnumerical characters together with the various punctuation marksrequired for alphanumeric printing. A solid line row 59a may be includedto print lines on the paper at any programmed time interval, wherebyguide, index or separation lines may be printed concurrently withprinting of the alphanumeric characters. In order to print properly, thecharacter-defining elements 59 are in mirror image form as viewed on theunderside of matrix member 43. It should be understood that theinvention is applicable to printing other types of character or forprinting numerical characters alone and may in fact be utilized to printpictorial or graphical data as will hereinafter be described.

In the present example, each row of character-defining elements 59 iscomposed of like characters and there is one row for each of thedifferent distinct characters which may be printed. It should beunderstood that this arrangement is also subject to variations. Ingeneral, to use the multiline parallelprinting technique, there must bea number of rows of character-defining elements 59 at least equal to thenumber of different characters which are to be printed. In the presentexample, there are 65 such rows to include all alphabetical andnumerical characters together with punctuation marks and each row has120 character-defining elements in conformity with the standard computerprintout format. However it is possible and often advantageous toutilize more than the minimum number of rows of character definingelements as will hereinafter be discussed. Further it is not strictlynecessary that each row be composed of like characters as the associatedcontrol circuitry can be programmed to adapt to other arrangements,provided that each column of characterdefining elements on the matrix 43contains at least one of each of the different distinct characters in atleast one of the rows transected by the columns. in other words, atleast one of each character must be provided in some one of the rows ateach of the 120 columns which extend parallel to the direction of papertravel. Generally, it is advantageous to utilize the present arrangementin which each row is composed of like characters in that the detectionand correction of malfunctions is simplified.

As described above, all character-defining elements 59 may be removedandreplaced as a unit by replacing the matrix member 43 and this ishighly advantageous when it is desired to change the type font or toadapt the mechanism to the printing of entirely different characters.However there are also instances where it is advantageous to be able toreplace one or more individual rows of character-defining elements 59.Certain specialized printing jobs for example may require a small numberof unusual characters such as certain Greek letters. In other instances,it may be observed that some particular character is not printingproperly due, for example, to a deformation of a particular characterdefining element 59 at the row corresponding to that character. Togreatly facilitate the removal and replacement of one or morecharacter-defining elements 59, each row thereof is formed along thelower surface of a rectangular bar 61 which extends transversely throughthe lower portion of the matrix member 53 in a conforming slot 62therein, the lower end of the bar being substantially at the lowersurface of the matrix member so that the associated character-definingelements 59 project slightly therebelow. To retain the bars 61 inposition in matrix member 43, the upper ends of the bars may have anenlarged portion 61' fitting in a correspondingly enlarged portion ofthe slots 62. The bars 61 are removable by being withdrawn sidewardlyfrom the matrix member 43 and for this purpose, as shown in FIG. 1, oneside of the housing 28 is provided with a hinged door 63 which may belifted to expose the ends of the bars. Door 63 has a handle 64 tofacilitate operation and a latch 66 to hold the door in the closedposition.

Referring now to FIG. 4, the ends of the bars 61 adjacent door 63project a small distance from the side of matrix member 43 and each suchprojecting portion of each bar has a transverse aperture 67 into which asuitable tool may be inserted to facilitate withdrawal of the bar fromthe matrix. Door 63 has a projection 68 on the inner side which bearsagainst the adjacent ends of the bars 61 when the door is closed andlatched to forestall shifting of the bars.

Referring now to FIGS. 2 and 4 in conjunction, the lower housing 26supports and positions a plurality of rows 69 of actuators forselectively causing any one of the previously describedcharacter-defining elements to imprint its character upon the paper 22.Each row 69 of actuator elements is a unitized assembly extendingparallel to an associated one of the rows of character-defining elements59 immediately below the paper 22 and ribbon 38. Each row 69 ofactuators has a plurality of flat headed hammers 71 equal in number tothe number of character-defining elements 59 in the corresponding rowwith each hammer being positioned to impress the paper and ribbonagainst an associated individual one of the character-defining elements.To receive and support the actuator row assemblies 69, housing 24 inthis example has a plurality of transverse vertical partitions 72adjacent ones being spaced apart to receive one of the actuator rowassemblies therebetween. Each such partition 72 has linear projections73 at the top and'bottom which overlap conforming shoulders on theadjacent actuator assemblies.

The above described unitized construction of each row 69 of actuators isa further highly valuable feature of the invention in that malfunctionsof an actuator are quickly and easily corrected. In particular, any ofthe actuator row assemblies 69 is removable as a unit in that it may bewithdrawn sidewardly from housing 28. For this purpose, as shown in FIG.I, a hinged door 74 is provided at one side of housing 24. Door 74 hashandles 76 to facilitate operation and a latch 77 holds the door closedunder normal conditions. Referring to FIG. 4. removal and replacement ofthe actuator row assemblies 69 is further facilitated in that the end ofeach assembly closest to door 74 projects a small distance theretowardsfrom the ends of housing partitions 72 whereby the actuator assembly mayreadily be gripped by a suitable tool. Door 74 is provided with aprojection 78 along the inner surface which bears against the exposedends of the actuator assemblies when the door is closed and latched toprevent any longitudinal shifting thereof.

Referring now to FIG. 5, important operational advantages of theinvention are realized by making each of the hammers 71 actuatableindependently of the actuation of other hammers in other rows thereof.If the hammers 71 of a plurality of rows must be actuated at preciselythe same time, then the line spacing of the printing on the paper isnecessarily fixed at the spacing of successive rows ofcharacter-defining elements. For structural reasons, this spacing isgenerally larger than the preferred spacing of successive lines ofprinting. This limitation is avoided by the present invention byutilizing an individual solenoid coil 79 to control each hammer togetherwith means for energizing any coil independently of the timing ofenergizing of the coils of other rows.

In order to drive the hammer 71, the solenoid 79 must usually have abulk exceeding the restricted space allotted to each hammer 71 along therow. FIG. illustrates still another important aspect of the inventionwhereby the necessary number of solenoids 79 are fitted into theunitized assembly 69 while providing for close spacing of the hammers 71and for desirably small character size and spacing.

Each actuator row assembly 69 has a rectangular casing 81 having a topplate 82 secured thereto. As best shown in FIG. 6, top plate 82 has anupwardly extending boss 83 along the central portion of the uppersurface thereof with a slot 84 extending therealong into which thehammers 71 fit in the retracted positions thereof.

Each hammer 71 is carried on the upper end of a driver member 86 whichextends downwardly to the associated solenoid coil 79. High-speedoperation requires fast-acting solenoids, and under some conditions thiscould result in a undesirably hard impact of the hammer 71 against thepaper 22 and overlying character-defining element 59. To forestalldifficulties of this kind, the hammer 71 may be formed of a slightlyresilient material such as a fairly stiff rubber. Further, to avoidinterference with the passage of paper through the printing station, thehammers 71 are formed with rounded edges facing the input and outputends of the printing station as shown in FIG. 6, and in their retractedpositions preferably do not project above the upper surface of the boss83.

Considering now the preferred disposition of the solenoids 79 within theassembly 69, with reference to FIGS. 5 to 8 in conjunction, theparticular solenoids used in this embodiment of the invention have adiameter substantially equal to the distance spanned by three of thecharacter positions along a row in a column of printing and thus cannotbe disposed in a simple side-by-side linear relationship. The desiredclose spacing of the hammers 71 is achieved by spacing each successiveseries of three solenoids 79 vertically as well as horizontally. Thus afirst solenoid at one end of the assembly 69 is situated below itsassociated hammer 71 and near the top of the casing 81. The solenoid 79'for the next hammer 71 is situated below the level of the first solenoid79 and is spaced horizontally therefrom so that it is directly below itsown hammer 71. Similarly the solenoid 79" for the third hammer 71 of therow is situated below the level of solenoid 79' and again it is spacedhorizontally therefrom. This sequence of vertical and horizontal spacingof the solenoids is then repeated for each successive group of threealong the row 69. It will be apparent that this basic form ofpositioning the solenoids can be utilized where the individual solenoidshave other porportions relative to the associated hammers 71. Thus ifrelatively smaller solenoids are used, the vertical spacing of thesolenoids into only two layers may be adequate while if relativelylarger solenoids are used each vertically spaced columns may includemore than three solenoids before the sequence is repeated along the row.

Referring now to FIGS. 6, 7 and 8 in conjunction with FIG. 5, theuppermost layer of solenoids 79 is supported by a member 87 whichextends along the row assembly 69 immediately below the upper mostsolenoids. Similarly, the intermediate layer of solenoids 79' issupported by a similar member 87' spaced below the first support member.The lowermost layer of solenoids 79" may be mounted directly in thefloor of casing 81. To provide adequate support without resorting tomassive construction of the support members 87 and 87, a series ofvertical posts 88 extend therebetween at intervals along the lengththereof and similar posts extend between the lower support member 87'and the floor of the casing 81. This is possible in that the dispositionof circular solenoids 79 in the described arrangement provides space forsuch vertical posts on either side of the points of contact of adjacentsolenoids.

Referring now to FIGS. 5 and 6 in conjunction, those of the hammerdrivers 86 which are associated with one of the top layers of solenoids79 may extend directly into the associated solenoid. To limit motion ofthe hammer driver 86 into the solenoid at a position at which theassociated hammer 71 is fully retracted against the floor of slot 84, apair of arms 89 extend sidewardly from the driver and abut against thetopmost surface of the solenoid. To provide for the desired upwardmotion of the driver 86 and hammer 71 when the solenoid is energized,the lowermost portion of driver 86 is an armature element 91 formed offerromagnetic material which may be fastened to the remainder of thedriver by threads 92. With the hammer 71 retracted as described above,the armature element 91 is preferably proportioned so that is upper endex tends a small distance into the solenoid '79. Thus when theassociated solenoid is energized, armature 91 is drawn upwardly andcarried driver 86 and hammer 71 in a similar direction. To insure fastretraction of the hammer 71 after the solenoid 79 is deenergized, acompression spring 93 is disposed around driver 86, in coaxialrelationship thereto, between the arm extensions 89 and the lowersurface of casing top member 83.

To provide for energizing of each solenoid coil 79, one of the leads 94therefrom extends upwardly to a metallic contact 96 in the shoulder ofthe top member 83. As shown in FIG. 2, contact 96 bears against theadjacent partition member 73 of housing 24 which is formed of conductingmaterial and which is grounded. The other solenoid lead 97 extendsdownwardly to a second contact 98 situated at the bottom surface ofcasing 81 as shown in FIG. 8 for coupling to energizing means as willhereinafter be described.

Referring now to FIG. 7 in particular, it is not possible to couple thesecond layer solenoids 79 to the associated hammers 71 and drivers 86 inthe same manner as is done for the top layer solenoids 79 as the toplayer solenoids intervene therebetween. This problem is resolved bycoupling the armature element 91 of each intermediate layer solenoid 79with its hammer driver 86 through a pair of staggered arms 99 and 101which extend around the intervening layer solenoid 79. Thus, each sucharm 99 and 101 extends sidewardly from driver 86 then downwardly, thenback under the upper layer solenoid 79 and support member 87 to connectwith the armature element 91 of the associated second layer solenoid79'. In order to provide space for the horizontal portions of the arms99 and 101 to travel upwardly and downwardly in response to energizationof the solenoid 79, the intermediate layer of solenoids 79' must bespaced an appropriate distance downward from the lower surface of uppersupport member 87.

Referring now to FIG. 8, the armature elements 91 associated with thelowermost layer of solenoids 79" connect with the corresponding hammerdrivers 86 through arms 102 and 103 which are staggered in a mannersimilar to that described with reference to FIG. 7, except that thevertical portions of the arms are of sufficient length to extend pastboth the upper layer of solenoids 79 and the intermediate layer ofsolenoids 79'. Again, the lowermost solenoids 79" must be spaced belowthe undersurface of lower support member 87, a distance sufficient toprovide for the desired travel of the arms 102 and 103.

Referring now again to FIGS. 2 and 4 in conjunction, the capability ofseparately energizing any one of the above described solenoids 79requires that a separate electrical connection be provided to eachindividual solenoid at the previously described metallic contacts 98which are distributed along the underside of the actuator row assembly69. Further, in keeping with a important object of the invention, thismust be provided for without complicating the removal and replacement ofthe actuator row assemblies. For this purpose, a unitized contact board104 is situated below housing 24 and is movable upwardly and downwardlyas a unit to open or close a separate connection with all solenoidssimultaneously. To receive the contact board 104, the support frame 26has a rectangular opening 106 beneath housing 24. An upright cylindricalguide 107 extends between the horizontal portion of the frame 26 and asupport bracket 108 near each corner of the opening 106 and contactboard 104 is provided with sleeve projections 109 at each corner whichengage the guides 107 and are slidable therealong in the verticaldirection.

As shown in FIG. 4, a shaft 111 extends beneath board 104 and isjournaled to opposite sides of the frame 26 to support a pair ofasymmetrical cams 112 which bear against the underside of the board. Oneend of shaft 111 projects through the side portion of frame 26 and ahandle 113, best shown in FIG. 1, is secured to the projecting end forturning the cams 1 12 to raise and lower the contact board. Handle 113may be provided with a latch 114 for fixing the angular position of thehandle at any of several desired positions to provide for vary ing thetension of spring contacts to be hereinafter described.

Referring now again to FIGS. 2 and 4, a plurality of C- shaped springcontacts 116 are secured to the top surface of contact board 104 in rowswhich are spaced similarly to the spacing of actuator row assemblies 69.Each such row includes a separate spring 116 positioned to contact eachof the superjacent contact elements 98 along the underside of theactuator row assembly 69. Thus, as the contact board 104 is raisedagainst the underside of housing 24 as previously described, each spring116 is compressed slightly to form a reliable connection with a separateone of the actuator solenoids. To connect to the associated controlcircuitry, each spring 116 has a conductor wire 117 coupled thereto, thewire preferably being imbedded within the board 104 which may be formedof cast plastic. At the underside of contact board 104 each wire 117couples to one of a plurality of disengageable multiconductor cable 118through a disengageable connection 119 which may be of the well-knownpin variety, for example.

Control circuitry suitable for operating a multiline parallel printoutmechanism from a serial form signal input is known to the art, andaccordingly, is indicated diagrammatically in FIG. 1. The coded inputsignals from computer 21 or other source are delivered to a temporarystorage 121 which may be comprised of flip-flop circuits, an array ofmagnetic cores or any of the other memory devices known to the art.Storage 121 is capable of storing a quantity of signals corresponding tothe total number of lines of printing which are within the printingstation 23 when the printout mechanism is adjusted to provide theminimum line spacing and is programmed to receive and store the signalsfor a new line while erasing the signals for a completed line each timethat the paper 22 advances through the printing station 23 a distanceequal to one line spacing of printing. As the paper 22 moves through theprinting station 23, a print logic circuit 122 receives a signal from aline signal generator 123 each time the paper has advanced one linespacing and upon receiving each such signal the logic circuit examinesthe data storage 121 to detect momentary coincidences between any of thecharacter defining elements 59 and a position on the paper whichrequires imprinting of the corresponding character. At each such cyclethe logic circuit 122 activates the appropriate ones of an array ofsolenoid drivers 123 each of which is coupled to a separate one of theactuator solenoids through the previously described cables 118 andassociated connections at the contact board 104. Each such solenoiddriver may be a solid-state switch or equivalent device known to the artfor supplying an energizing current impulse to the associated solenoid.

The print logic 122 and data storage 121 are shown apart from thecomputer 21 in FIG. 1 to facilitate an understanding of the control ofthe mechanism and in some instances these components are physicallydistinct from the data source such as computer 21. However, it will beapparent that the functions of the data storage 121 and print logic 122can be performed by an appropriately programmed computer 21 which isalso the source of the data to be printed. This is usually the preferredmode of operation where adequate computer capacity is available.

Unlike prior multiline parallel printing systems, the cycling rate ofthe logic circuit 122 is not necessarily matched to the rate at which agiven line on the paper passes successive rows of imprinting elements.Such a cycling rate provides for only one line spacing of the printingand this is necessarily fixed at the spacing between successive rows ofimprinting elements. Because of mechanical consideration, this spacingof the rows of imprinting elements is generally larger than thepreferred line spacing of printing. This limitation is avoided in thepresent invention by cycling the logic circuit 122 a plurality of timesduring the interval required for a given line on the paper to advancefrom one row of imprinting elements to the next. In particular, thedesired line spacing is selected and then the logic circuit 122 iscycled at a rate which provides for a cycle each time any line on thepaper is at any one of the rows of imprinting elements. This not onlyprovides for a closer line spacing of imprinting but also provides forselectively varying the line spacing through appropriate changes in thecycling rate of the logic circuit 122. It should be observed that thereis no mechanical constraint in the above described construction of theprintout mechanism which prevents this mode of operation. There is nolimitation in the mechanical or electrical system which requires thatthe character-imprinting elements 59 of more than one row thereof beactuated precisely at the same instant.

As discussed above, the logic circuit 122 cycles each time a line signalis received from a line signal generator 123 which clocks the movementof paper 22 through the printing station 23. Thus line signal generator123 must deliver a line signal to logic circuit 122 each time that anyline on the paper is at any row of imprinting elements and therepetition rate of these line signals relative to paper speed must bechanged if the line spacing is to be changed as discussed above.

To provide for this, the line signal generator 123 may be a pulsefrequency divider which receives input pulses from a photoelectric tube124. Phototube 124 views a light source 126 through a rotating opaquedisc 127 having a series of light transmissive windows 128 equiangularlyspaced therearound at a radius which provides for the periodic momentarytransmission of light from source 126 to the phototube. Disc 127 isdriven by one of the paper drive rollers 33 through a speed-increasinggearbox whereby the frequency of input pulses to the line signalgenerator 123 is determined by the speed of paper 22 which itself may befreely changed by the paper speed control 37. In order to provide anoutput or line signal at any selected one of a series of differentrepetition rates relative to paper speed, line signal generator 123 maybe a counter-divider of known construction which divides the inputsignal frequency by a factor determined by the selected setting of amultiple position control switch 129. Thus, at any given paper speed,line signal generator 123 may be adjusted at switch 129 to cycle printlogic 122 at a repetition rate needed to effect any one of a series ofdifferent line spacings of printing on the paper 22.

The construction of the printing mechanism may be modified and varied indifferent ways to meet specialized operating conditions and requirementswhile utilizing basic features of the invention. FIG. 9, for example,illustrates two modifications with respect to mounting the characterdefining elements 59 on the undersurface of the unitized stationarytypematrix 43a. For greatest simplicity, the character-defining elements maybe formed as an integral part of the under-' surface of the type matrix430, by casting for example, as illustrated at 59' in FIG. 9. Thecharacter-defining elements 59' may all be formed in this manner or thisconstruction may be used with one or more of the replaceable bar insertsheretofore described to provide for some variation of the printingobtainable from the matrix. A second row of character-defining elements59 is shown in FIG. 9 as carried on a specialized removable bar 61'which is capable of a limited amount of yieldability in the direction ofpaper travel as indicated by arrow 36. This construction may bedesirable when printing at extremely high speeds in that at varioustimes a large number of the hammers 71 may be actuated and may besimultaneously compressing the paper 22 and ribbon 38 against thesuprajacent stationary character defining elements 59 and the slightflexibility imparted to the latter will avoid impeding the travel of thepaper and ribbon to the point where difficulties could occur. Theresiliently positioned insert 61 may be of essentially similarconstruction to that previously described except that it is of slightlyless width in the direction of paper movement than the slot 62' in thetype matrix 43 in which it is received and the additional space thuscreated is filled with a thin flat backing strip 136 of resilientmaterial such as rubber. Thus the associated character-defining elements59" may advance a small amount with the paper 22 if necessary during theactuation of the hammers 71 in the associated row thereof and will besubsequently restored to its initial position after the hammers retractby the resiliency of backing strip 136. To provide for this motion, thewidened upper end of the replaceable bar insert 61" is of circular crosssection in this instance.

Referring now to FIG. 10, a modification of the invention is illustratedwhich provides for a simplified single layer disposition of thesolenoids 79 which serve as actuators for the character-imprintingelements 59. This is effected by providing several successive rows ofcharacter-defining elements 59, all of which carry the same characterand which are spread apart a distance sufficient to provide for thedisposition of the solenoids 79 in a single layer both in the directionof paper travel 36 and at right angles thereto. The individualcharacterdefining elements 59 of each row are offset one column spacewith respect to the like character-defining elements of the adjacentrows and, in the example illustrated in FIG. 10, four rows of eachdistinct kind of character-defining element are provided. This of courserequires a type matrix element 43b which is elongated in the directionof paper travel relative to the previously described embodiment but thisincrease in size may in some cases be justified by the simplification inthe mounting of solenoids 79.

In a printout system of the kind described above, printing speed mayultimately be limited by the recovery time of individual actuators sinceany particular actuator and its associated imprinting elements may berequired to print its character at the same column position in twosuccessive lines of printing and if the second of the two lines on thepaper passes the particular actuator before it has recovered and isready to operate again the desire printout cannot be successfullyaccomplished. It should be understood that this limitation on printingspeed still provides for much higher printout speeds than are realizedwith the commonly used existing apparatus. Nevertheless it is of coursedesirable to increase printing speed even more and FIG. 11 illustrates amodification of the invention which removes actuator recovery time as alimiting factor in printing speed.

In the arrangement of FIG. 11, the type matrix 43c is provided with tworows of identical character-defining elements 59 for each distinctcharacter to be printed with both of the two rows providing thecharacter for all column positions and each having its row assembly ofactuator solenoids 79 which may be arranged as hereinbefore described.In this construction, the control circuit is arranged to utilize one rowto print a first character of a given type and then to utilize the otherrow of the same characters to print the next character of the same typewhich occurs in that column position. The practical effect of this isthat the same character can be printed at the same column position intwo successive lines of printing without waiting for the solenoid whichprinted the first character to recover. In other words, the twosolenoids 79 capable of printing the same character at the same columnposition on the paper are used alternately for that purpose. Thisprovides for printing the same character in two lines in succession in atime equal to one-half the recovery item of a specific solenoid. It willbe apparent that if still greater printing speeds are called for,additional rows of the same character-defining elements may be providedas necessary.

The arrangement of the control circuitry to alternately make use of twodifferent solenoids capable of imprinting at the same column position onthe paper may be achieved in various ways and FIG. 11 illustrates onesuch arrangement wherein the extra row of solenoids for each distinctcharacter, taken in combination constitute in effect a second duplicateprintout system which is used for each alternate cycle of operation. Inparticular, the solenoids 79 of a first row thereof for each characterare coupled to a first set of solenoid drivers a controlled by a firstlogic circuit 122a as previously described and the alternate row ofsolenoids for the same character has solenoid drivers 125b controlled bythe duplicate logic circuit l22b. Both logic circuits 122a and 1221) mayinterrogate the same data storage 1210 which received the input signalsfrom the computer 21 or other source. To alternately cycle the twosystems, a gate 137 directs even line signals from generator 123 to onelogic circuit 125a and directs the alternate or odd line signals tologic circuit 125 b. Since the extra row of imprinting elements for eachcharacter is displaced from the primary row to which the line signalsare referenced, it is necessary that the solenoid-energizing signalswhich are directed to the other row be delayed for the time required forthe paper to travel between the two rows. For this purpose a variabletime delay circuit is situated between gate 137 and the print logic l22bof the alternate system. Time delay 140 thus functions to deferoperation of the solenoids 79 of the extra rows until the line on thepaper has moved to the extra row of character-imprinting elements 59.Since this time is a function of the paper speed, which is itselfvariable, time delay circuit 140 is controlled by a signal indicative ofpaper speed which may be derived from an output terminal 141 atphototube 124 as shown in FIG. 1. It should be understood that thetime-delaying function can be performed at any of various other pointsin the alternate control system comprised of logic 122b and solenoiddrivers 125k.

The invention may also be adapted to the printout of pictorial orgraphical data either by itself or in combination with alphanumerictext. FIG. 12, for example, illustrates a type matrix member 43d asmodified for such printing. The matrix member 43d includes thealphanumeric character defining elements 59 as hereinbefore describedand in addition carries a plurality of rows of dot-defining elements 142each having an actuator solenoid 79 associated therewith in the mannerhereinbefore described. The dot-defining elements 142 of each row areoffset, in a direction transverse to the paper travel 36, from the dotelements of the adjacent rows by a distance equal to the total columnwidth divided by the number of rows of dot-defining elements. Five suchrows are employed in the present instance with the dots of each rowbeing offset from those of the adjacent rows by one-fifth of thetransverse spacing of adjacent dot-defining elements in any one row.Each dot-defining element preferably has a diameter of about one-fifthof the above described spacing between dots in a particular single row.This arrangement of dot-defining elements 140 allows an image to beimprinted on paper, in a parallel fashion, by printing dots to definedark areas as the paper travels along the rows of dot-defining elements.Scanning devices which translate a printed image into serial signalsindicative of image density at each incremental area of the image areknown to the art and are used for example in wire photosystems. Codedoutput signals from such a device may be processed to operate the dotmatrix 43d essentially as hereinbefore described for alphanumericprintout.

If greater image definition is desired than is afforded by the dot sizeof the above described construction, the diameter of the dot-definingelements 142 may be reduced and an ap- .propriately larger number ofrows of such elements may be provided. Similarly, if faster imageprintout is required, the sequence of rows of dot-defining elements 142may be repeated one or more times rather than utilizing the singlesequence of five as illustrated in FIG. 12.

Basic aspects of the invention may be utilized in printout mechanismswhich employ fundamentally different means for imprinting characters onthe paper. Referring now to FIG. 13, an embodiment of the invention isshown in which electrostatic printing is employed. The printing station144 region in this embodiment requires no moving parts whatsoever otherthan the paper 22 itself.

The printing station 144 in this instance is comprised of a connectorboard 146, an imprinting element matrix 147 situated immediatelythereabove and a backing electrode member 148 which is uppermost. Board146, matrix 147 and electrode member 148 are each of flat rectangularconfiguration and are secured to a subjacent frame 149 by upright bolts151 which extend through the corners of each member. Paper 22 is of thecoated type suitable for electrostatic printing and is movedcontinuously between matrix 147 and electrode member 148 by a suitabledrive system which may, for example, consist of paired rollers driven bya variable speed motor 153 through a speed reduction mechanism 154. lnthe embodiment of the invention shown inFlG. 13, the drive rollers 152are arranged to carry the paper 22' horizontally through the printingstation and then around a drum 157 of a developing station and thenupwardly past a viewing window 158 in a suitable housing 159. The papermay then be traveled horizontally again back over the printing station152 to suitable paper takeup means.

Referring now to FIG. 14, the paper 22 passes along an array of mirrorimage character defining elements 161 which in this instance aresituated immediately under the paper on the top surface of matrix 147and which are arranged in rows of like character-defining elementsincluding at least one row of each character which it may be desired toprint. Owing to the absence of electromagnetical actuators, the rows ofcharacter-defining elements 161 in this instance may be closely spacedand the assembly as a whole may be relatively compact.

Referring now to FIG. 15, each character-defining element 161 is theenlarged upper end of a pin 162 which constitutes the actuator in thisembodiment and which has a lower end that projects from the bottomsurface of the matrix 147 to form the male element of a pin connector.Each of the pins 162 including character-defining elements 161 must beelectrically insulated from each of the others and this isadvantageously provided for by forming the matrix member 147 of asuitable insulative plastic which can simply be cast around the array ofcharacter-defining elements to form a solid integral unit therewith.

A separate electrical connection to each of the characterdefiningelements 161 is provided for by a matching array of female pin connectorelements 163 each adapted to engage with a separate one of theprojecting lower ends of pins 162. The highly desirable unitized solidconstruction is again provided for by casting the connector board 146 ofinsulative plastic aroundthe arrayof female connector elements 163 toform an integral structure therewith. Within the lower portion ofconnector board 146, an individual lead wire 164 connects each femaleelement 163 with one of a plurality of multiconductor cables 166,suitable holes 167 being provided in frame 149 to receive the connectorelement 168 at the end of each cable.

Referring still to FIG. 15, the backing electrode member 148 has a flatplate 169 disposed parallel to the upper surface of matrix 147 andspaced a small distance therefrom to form a thin passageway 171for thepaper 22'. As shown in FIG. 14, this spacing is provided for by a thinspacer element 172 disposed between matrix 147 and plate 169 along eachside thereof, the spacers being transpierced by the bolts 151 whichsecure the entire assembly together. It will be apparent that the spacerelements 172 may be removed and replaced with thinner or thickerelements as desired to adjust the height of the paper passage 171.

Referring now again to FIG. 15, effective electrostatic printingrequires that the paper 22 be kept from undergoing slight oscillationsin the vertical direction relative to the characterdefining elements 161and backing electrode plate 169 and to assure that uniform paperposition is maintained at extreme high speeds, it may be desirable toprovide a vacuum means for holding the paper flat against one of theelements. Thus a series of narrow passages 173 may be provided throughthe backing electrode plate 169, each beingiat the interstice betweenfour of the character-defining elements 161 so that the absence ofconductive metal at these points will not inter fere with electrostaticimprinting by distorting the electrical fields. The backing electrodemember 148 includes a top plate 174 spaced above plate 169 to form aplenum region 176 therebetween. Referring now to FIG. 13 in conjunctionwith FIG. 15, an air pump 177 has an intake coupled to the plenum region176 to draw air therefrom and thus to draw air through the passage 173in electrode plate 169 and thereby maintain the paper 22' flat againstthe plate. Pump 177 is preferably coupled to plenum region 176 throughmanifolding 178 formed on the top plate 174 to assure a reasonablyuniform negative air pressure at all regions of the backing electrodemember.

Referring now to P16. 15, a selected individual characterdefiningelement 161 may be caused to imprint its character upon the paper 22 byapplying a high voltage electrical signal to the element. The paper 22is of a type having a coating which will receive and retain anelectrical charge having a configuration conforming to the character tobe printed. Thus when a voltage pulse, typically of several hundredvolts magnitude, is applied to any selected one of thecharacter-defining elements 161, an electrical field is created betweenthe character-defining element and backing electrode plate 169 andelectrical charges are imparted to an area of the adjacent surface ofthe paper with the charged area having a configuration conforming to thedesired character. Referring now again to FlG. 13, the paper 22' emergesfrom the printing station 144 with the appropriately charged areas atthe underside of the paper and passes around drum 157 as previouslydescribed at which region the charged underside of the paper is exposedto a developing solution 179. The developing solution is a liquidsuspension of. visible pigment particles which are elcctrostaticallyattracted to the charged areas of the paper and which are retainedthereat as the paper emerges from the solution. The printing is thusdefined on the surface of paper 22' in a visible manner and the pigmentparticles are permanently bonded thereto as the paper dries during itspassage upwardly and backwardly from the developer.

The mechanism for exposing the charged paper to the developing solutionmay be of essentially conventional construction and thus may include atank 181 having one side conforming to an adjacent portion of drum 157with an opening 182 thereat whereby the solution within the tankcontacts the paper as his carried around the drum. To avoid leakage. aslight degree of vacuum may be maintained within the tank 181 by a pump183.

Control circuitry for the electrostatic system of FIG. 13 may beessentially similar to that hereinbefore described with reference to theelectromechanical printout mechanism except insofar as the electricalprint impulses which are transmitted to the individualcharacter-imprinting means are of higher voltage. Thus the serial formoutput signals from a computer 21' or readout device are transmitted toa temporary data storage 121' which is repetitively scanned by a printlogic circuit 122'. at a rate determined by a cyclical signal from anadjustable line signal generator 123'. As in the previous instance,print logic 122 activates the appropriate ones of a plurality ofhighvoltage drivers each of which is connected to a separate one of thecharacter-defining elements 161 through the cables 166, upon detectingcoincidences between a position on the paper and an imprinting element161 corresponding to a character to be printed at such position. Thevariable line signal generator 123 may again be controlled by a rotarydisc 127 coupled to one of the drive rollers 152 through speedincreasing device 130' and having a series of light transmissive areas128 around the periphery for transmitting pulses of light between asource 126' and phototube 124 with a frequency which is a function ofthe paper speed as determined by the setting of the variable speed drivemotor 153.

Thus many modifications and variations are possible within the scope ofthe invention, and it is not intended to limit the invention except asdefined in the following claims.

1. Apparatus for printing from coded signals that identify specific onesof a plurality of distinct characters to be printed, comprising:

an array of character-defining elements arranged in a plurality of rowsand columns, each column containing at least one of each of saiddistinct characters;

means for moving a recording web along said array of character-definingelements in a direction parallel to said columns thereof,

an array of actuator elements each being associated with a separate oneof said character-defining elements for causing the associatedcharacter-defining element to impart its character to said recordingweb, said actuator elements of any row being energizable independentlyof the timing of energization of the actuator element of other rows,

a data storage receiving and temporarily storing said coded signals, and

control means for repetitively examining said data storage to detectcoincidences between the momentary position of an area of said recordingweb and a character-defining element corresponding to a character whichis to be imprinted thereat, said control means energizing thecorresponding ones of said actuator elements upon detection of saidcoincidences, and wherein said control means cyclically repeats saidexamination of said data storage and energization of appropriate ones ofsaid actuators more than once while a given line of printing on saidrecording web moves from a given row of said characterdefining elementsto the adjacent row thereof 2. Apparatus as defined in claim 1 furthercomprising a line signal generator producing a line signal in responseto predetermined increments of movement of said paper past said array ofcharacter-defining elements, and wherein said control means is coupledto said line signal generator and con trolled thereby to repetitivelyexamine said memory and energize appropriate ones of said actuators inresponse to said line signals from said generator.

3. Apparatus as defined in claim 2 wherein said line signal generatorproduces said line signals at intervals which are less than the timerequired for a given point on said web to travel from one row of saidcharacter-defining elements to the next row thereof.

4, Apparatus as defined in claim 2, wherein said line signal generatorhas a control for selectively changing the repetition rate of said linesignals relative to the time interval required for a point on said webto move from one of said rows of character-defining elements to the nextrow thereof whereby the spacing of lines of printing on said recordingweb may be selectively changed.

5. Apparatus as defined in claim 1 having a line signalproducing meanscoupled to said control means for producing line signals which determinethe cycling rate at which said control means examines said data storageand actuates appropriate ones of said actuator elements, said linesignalproducing means comprising:

a rotatable element coupled to said means for moving said web wherebysaid rotatable element rotates in synchronism with the movement of saidweb and at a rate proportional to the speed of said web,

0 identify distinct characters to be printed in a plurality of lines ofprinting on a moving recording web, an array of characterimprintingmeans and supporting means therefor, said character-imprinting means andsupporting means therefor, said character-imprinting means beingarranged in rows and columns with said columns being aligned with thedirection of movement of said recording web and wherein at least oneimprinting means corresponding to each distinct character is present ineach column in at least one of the rows transected thereby, saidcharacter-imprinting means each being comprised of a stationarycharacter-defining element having a configuration conforming to thecorresponding character and having an individually energizable actuatortherefor, wherein a plurality of said character-defining elements areformed as integral portions of a single member which carries allcharacter-defining elements for an entire row thereof and is removablefrom said supporting means independently of other rows ofcharacter-defining elements.

7. Apparatus for printing from coded signals which identify distinctcharacters to be printed in a plurality of lines of printing on a movingrecording web comprising an array of character-imprinting means arrangedin rows and columns with said columns being aligned with the directionof movement of said recording web and wherein at least one imprintingmeans corresponding to each distinct character is present in each columnin at least one of the rows transected thereby, saidcharacter-imprinting means each being comprised of a stationarycharacter-defining element having a configuration conforming to thecorresponding character and an individually energizable actuatortherefor, wherein a plurality of said actuator elements are secured to asingle support member whereby said plurality of actuator elements may beinstalled and removed as a unit.

8. Apparatus as defined in claim 7 wherein said plurality of actuatorelements which are secured to a single support member comprise all theactuators for a row of said characterdefining elements.

9. Apparatus for printing from coded signals which identify distinctcharacters to be printed in a plurality of lines of printing on a movingrecording web comprising an array of character-imprinting means arrangedin rows and columns with said columns being aligned with the directionof movement of said recording web and wherein at least one imprintingmeans corresponding to each distinct character is present in each columnin at least one of the rows transected thereby, saidcharacter-imprinting means each being comprised of a stationarycharacter-defining element having a configuration conforming to thecorresponding character and an individually energizable actuator elementtherefor, said actuator elements being of the electrically energizedform said apparatus further having a unitized connector board memberdisposable against a plurality of said actuator elements and carrying atleast one individual electrical contact for coupling to each of saidplurality of actuator elements whereby electrical connection to all saidplurality said plurality of actuators maybe made simultaneously bydisposition of said board against said actuators.

10. Apparatus for printing from coded signals which are indicative of aplurality of distinct characters to be printed comprising:

a type matrix having a flat surface with a plurality of stationarycharacter-defining elements thereon, said character-defining elementsbeing arranged on said surface in a plurality of rows and columns,

drive means for traveling a recording medium along said surface, saidrecording medium being parallel to said surface and moving in adirection normal to said rows of character-defining elements thereof,

a flat support means carrying a plurality of electrically energizableactuator elements being each associated with a specific one of saidcharacter-defining elements to transfer the character defined thereby tosaid recording medium,

a connector board disposable at said support means in parallelrelationship thereto and carrying a plurality of electrical connectormeans each being positioned to connect with a separate one of saidactuator elements when said board is disposed at said support means, and

control circuitry receiving and temporarily storing said coded signalsfor a plurality of lines for printing, said control means being coupled'to said connector board for energizing appropriate ones of said actuatorelements therethrough as said recording medium travels past said matrix.

11. Printout mechanism operating from coded input signals which identifyspecific ones of a plurality of distinct characters to be printed,comprising:

a fixed array of stationary character-defining elements arranged in aplurality of rows and columns with at least one element defining each ofsaid distinct characters being in each of said columns in at least oneof the rows transected thereby, each of said character-defining elementshaving a projecting portion shaped in conformity with the characterdefined thereby,

drive means for traveling a recording web past said array ofcharacter-defining elements along a path at which said recording web isparallel to said array and moves in a direction parallel to the columnsof character-defining elements, and

plurality of actuator elements disposed in a matching array of rows andcolumns on the opposite side of the path of travel of said recording webfrom said array of character-defining elements, each of said actuatorelements having a flat-headed movable hammer and a separatelyenergizable electrical drive means therefor for impressing saidrecording web against the projecting portion of the associated characterdefining element, wherein said electrical drive means of said actuatorsare comprised of solenoid coils having movable cores of ferromagneticmaterial coupled to said hammers and wherein a plurality of saidsolenoid coils are joined together in a unitized group which may beremoved from said mechanism independently of others of said solenoids.l2. Printout mechanism as defined in claim 11 wherein said plurality ofsolenoid coils joined together in a unitized group comprises allsolenoid coils associated with a row of said character-definingelements, said solenoid coils being disposed within a housing havingtransverse guide means therein for receiving said unitized row thereofmay be removed by being withdrawn sidewardly from said housing withoutremoving other rows of solenoid coils.

13. Printout mechanism as defined in claim 12 wherein said unitized rowof solenoid coils is carried in a casing having a plurality of contactstherealong each electrically connected with a separate one of thesolenoid coils of said row, said mechanism further comprising a contactboard disposed adjacent said unitized row of solenoid coils and having aplurality of spring contacts positioned therealong to connect withindividual ones of said solenoid coil contacts, and mechanism forselectively impressing said contact board against said unitized row ofsolenoid coils and for retracting said contact hoard therefrom tofacilitate said removal of said unitized row of solenoid coils.

l4. Printout mechanism operating from coded input signals which identifyspecific ones of a plurality of distinct characters to be printed,comprising:

a fixed array of stationary character-defining elements arranged in aplurality of rows and columns with at least one element defining each ofsaid distinct characters beings in each of said columns in at least oneof the rows transected thereby, each of said character-defining elementshaving a projecting portion shaped in conformity with the characterdefined thereby,

drive means for traveling a recording web past said array ofcharacter-defining elements along a path at which said recording web isparallel to said array and moves in a direction parallel to the columnsof character-defining elements, and

a plurality of actuator elements disposed in a matching array of rowsand columns on the opposite side of the path of travel of said recordingweb from said array of character-defining elements, each of saidactuator elements having a flat-headed movable hammer and a separatelyenergizable electrical drive means therefor for impressing saidrecording web against the projecting portion of the associated characterdefining element,

wherein said electrical drive means for said hammers are of greaterextent in a direction parallel to said rows than said hammers andwherein a sequence of successive ones of said electrical drive meansalong said row of actuators are spaced from the associated hammer byprogressively greater amounts and wherein said sequence is repeatedalong said row.

15. Printout mechanism as defined in claim 14 wherein said drive meansare comprised of solenoid coils driving a movable armature and each ofsaid hammers is coupled to the associated one of said drive means by adriver member extending therebetween wherein the driver membersassociated with those of the drive means which are separated from theassociated hammer by an intervening one of the other drive means have anangled configuration and extend around said intervening drive means.

16. Printout mechanism operating from coded input signals which identifyspecific ones of a plurality of distinct characters to be printed,comprising:

a fixed array of stationary character-defining elements arranged in aplurality of rows and columns with at least one element defining each ofsaid distinct characters being in each of said columns in at least oneof the rows transected thereby, each of said character-defining elementshaving a projecting portion shaped in conformity with the characterdefined thereby,

drive means for traveling a recording web past said array ofcharacter-defining elements along a path at which said recording web isparallel to said array and moves in a direction parallel to the columnsof character-defining elements, and

a plurality of actuator elements disposed in a matching array of rowsand columns on the opposite side of the path of travel of said recordingweb from said array of character-defining elements, each of saidactuator elements having a flat-headed movable hammer and a separatelyenergizable electrical drive means therefor for impressing saidrecording web against the projecting portion of the associatedcharacter-defining element,

wherein said electrical drive means of each of said actuators has agreater extent along said rows than the associated hammer, and whereinsaid array of character-defining elements has a plurality of rows oflike character-defining elements with each successive row thereof beingoffset from the adjacent rows in a direction transverse to the travel ofsaid recording web and with the character-defining elements of each rowbeing spaced apart by a plurality of column spaces, said electricaldrive means of said ac tuators for each distinct character beingcorrespondingly arranged in a plurality of rows, whereby said electricaldrive means of said actuators may be equidistantly spaced from saidarray of character-defining elements.

1. Apparatus for printing from coded signals that identify specific onesof a plurality of distinct characters to be printed, comprising: anarray of character-defining elements arranged in a plurality of rows andcolumns, each column containing at least one of each of said distinctcharacters; means for moving a recording web along said array ofcharacterdefining elements in a direction parallel to said columnsthereof, an array of actuator elements each being associated with aseparate one of said character-defining elements for causing theassociated character-defining element to impart its character to saidrecording web, said actuator elements of any row being energizableindependently of the timing of energization of the actuator element ofother rows, a data storage receiving and temporarily storing said codedsignals, and control means for repetitively examining said data storageto detect coincidences between the momentary position of an area of saidrecording web and a character-defining element corresponding to acharacter which is to be imprinted thereat, said control meansenergizing the corresponding ones of said actuator elements upondetection of said coincidences, and wherein said control meanscyclically repeats said examination of said data storage andenergization of appropriate ones of said actuators more than once whilea given line of printing on said recording web moves from a given row ofsaid characterdefining elements to the adjacent row thereof. 2.Apparatus as defined in claim 1 further comprising a line signalgenerator producing a line signal in response to predeterminedincrements of movement of said paper past said array ofcharacter-defining elements, and wherein said control means is coupledto said line signal generator and controlled thereby to repetitivelyexamine said memory and energize appropriate ones of said actuators inresponse to said line signals from said generator.
 3. Apparatus asdefined in claim 2 whereiN said line signal generator produces said linesignals at intervals which are less than the time required for a givenpoint on said web to travel from one row of said character-definingelements to the next row thereof.
 4. Apparatus as defined in claim 2wherein said line signal generator has a control for selectivelychanging the repetition rate of said line signals relative to the timeinterval required for a point on said web to move from one of said rowsof character-defining elements to the next row thereof whereby thespacing of lines of printing on said recording web may be selectivelychanged.
 5. Apparatus as defined in claim 1 having a linesignal-producing means coupled to said control means for producing linesignals which determine the cycling rate at which said control meansexamines said data storage and actuates appropriate ones of saidactuator elements, said line signal-producing means comprising: arotatable element coupled to said means for moving said web whereby saidrotatable element rotates in synchronism with the movement of said weband at a rate proportional to the speed of said web, pulse-generatingmeans having an input controlled by said rotatable element forgenerating said line signals at a repetition rate determined by theangular speed of said rotatable element, and means for selectivelychanging the number of said line signals produced by saidpulse-generating means in response to a given increment of rotation ofsaid rotatable element.
 6. In an apparatus for printing from codedsignals which identify distinct characters to be printed in a pluralityof lines of printing on a moving recording web, an array ofcharacter-imprinting means and supporting means therefor, saidcharacter-imprinting means and supporting means therefor, saidcharacter-imprinting means being arranged in rows and columns with saidcolumns being aligned with the direction of movement of said recordingweb and wherein at least one imprinting means corresponding to eachdistinct character is present in each column in at least one of the rowstransected thereby, said character-imprinting means each being comprisedof a stationary character-defining element having a configurationconforming to the corresponding character and having an individuallyenergizable actuator therefor, wherein a plurality of saidcharacter-defining elements are formed as integral portions of a singlemember which carries all character-defining elements for an entire rowthereof and is removable from said supporting means independently ofother rows of character-defining elements.
 7. Apparatus for printingfrom coded signals which identify distinct characters to be printed in aplurality of lines of printing on a moving recording web comprising anarray of character-imprinting means arranged in rows and columns withsaid columns being aligned with the direction of movement of saidrecording web and wherein at least one imprinting means corresponding toeach distinct character is present in each column in at least one of therows transected thereby, said character-imprinting means each beingcomprised of a stationary character-defining element having aconfiguration conforming to the corresponding character and anindividually energizable actuator therefor, wherein a plurality of saidactuator elements are secured to a single support member whereby saidplurality of actuator elements may be installed and removed as a unit.8. Apparatus as defined in claim 7 wherein said plurality of actuatorelements which are secured to a single support member comprise all theactuators for a row of said character-defining elements.
 9. Apparatusfor printing from coded signals which identify distinct characters to beprinted in a plurality of lines of printing on a moving recording webcomprising an array of character-imprinting means arranged in rows andcolumns with said columns being aligned with the direction of movementof said recording web and wherein at least onE imprinting meanscorresponding to each distinct character is present in each column in atleast one of the rows transected thereby, said character-imprintingmeans each being comprised of a stationary character-defining elementhaving a configuration conforming to the corresponding character and anindividually energizable actuator element therefor, said actuatorelements being of the electrically energized form, said apparatusfurther having a unitized connector board member disposable against aplurality of said actuator elements and carrying at least one individualelectrical contact for coupling to each of said plurality of actuatorelements whereby electrical connection to all of said plurality saidplurality of actuators maybe made simultaneously by disposition of saidboard against said actuators.
 10. Apparatus for printing from codedsignals which are indicative of a plurality of distinct characters to beprinted comprising: a type matrix having a flat surface with a pluralityof stationary character-defining elements thereon, saidcharacter-defining elements being arranged on said surface in aplurality of rows and columns, drive means for traveling a recordingmedium along said surface, said recording medium being parallel to saidsurface and moving in a direction normal to said rows ofcharacter-defining elements thereof, a flat support means carrying aplurality of electrically energizable actuator elements each beingassociated with a specific one of said character-defining elements totransfer the character defined thereby to said recording medium, aconnector board disposable at said support means in parallelrelationship thereto and carrying a plurality of electrical connectormeans each being positioned to connect with a separate one of saidactuator elements when said board is disposed at said support means, andcontrol circuitry receiving and temporarily storing said coded signalsfor a plurality of lines of printing, said control means being coupledto said connector board for energizing appropriate ones of said actuatorelements therethrough as said recording medium travels past said matrix.11. Printout mechanism operating from coded input signals which identifyspecific ones of a plurality of distinct characters to be printed,comprising: a fixed array of stationary character-defining elementsarranged in a plurality of rows and columns with at least one elementdefining each of said distinct characters being in each of said columnsin at least one of the rows transected thereby, each of saidcharacter-defining elements having a projecting portion shaped inconformity with the character defined thereby, drive means for travelinga recording web past said array of character-defining elements along apath at which said recording web is parallel to said array and moves ina direction parallel to the columns of character-defining elements, anda plurality of actuator elements disposed in a matching array of rowsand columns on the opposite side of the path of travel of said recordingweb from said array of character-defining elements, each of saidactuator elements having a flat-headed movable hammer and a separatelyenergizable electrical drive means therefor for impressing saidrecording web against the projecting portion of the associated characterdefining element, wherein said electrical drive means of said actuatorsare comprised of solenoid coils having movable cores of ferromagneticmaterial coupled to said hammers and wherein a plurality of saidsolenoid coils are joined together in a unitized group which may beremoved from said mechanism independently of others of said solenoids.12. Printout mechanism as defined in claim 11 wherein said plurality ofsolenoid coils joined together in a unitized group comprises allsolenoid coils associated with a row of said character-definingelements, said solenoid coils being disposed within a housing havingtransverse guide means therein for receiving said uNitized row ofsolenoid coils whereby said unitized row thereof may be removed by beingwithdrawn sidewardly from said housing without removing other rows ofsolenoid coils.
 13. Printout mechanism as defined in claim 12 whereinsaid unitized row of solenoid coils is carried in a casing having aplurality of contacts therealong each electrically connected with aseparate one of the solenoid coils of said row, said mechanism furthercomprising a contact board disposed adjacent said unitized row ofsolenoid coils and having a plurality of spring contacts positionedtherealong to connect with individual ones of said solenoid coilcontacts, and mechanism for selectively impressing said contact boardagainst said unitized row of solenoid coils and for retracting saidcontact board therefrom to facilitate said removal of said unitized rowof solenoid coils.
 14. Printout mechanism operating from coded inputsignals which identify specific ones of a plurality of distinctcharacters to be printed, comprising: a fixed array of stationarycharacter-defining elements arranged in a plurality of rows and columnswith at least one element defining each of said distinct charactersbeings in each of said columns in at least one of the rows transectedthereby, each of said character-defining elements having a projectingportion shaped in conformity with the character defined thereby, drivemeans for traveling a recording web past said array ofcharacter-defining elements along a path at which said recording web isparallel to said array and moves in a direction parallel to the columnsof character-defining elements, and a plurality of actuator elementsdisposed in a matching array of rows and columns on the opposite side ofthe path of travel of said recording web from said array ofcharacter-defining elements, each of said actuator elements having aflat-headed movable hammer and a separately energizable electrical drivemeans therefor for impressing said recording web against the projectingportion of the associated character defining element, wherein saidelectrical drive means for said hammers are of greater extent in adirection parallel to said rows than said hammers and wherein a sequenceof successive ones of said electrical drive means along said row ofactuators are spaced from the associated hammer by progressively greateramounts and wherein said sequence is repeated along said row. 15.Printout mechanism as defined in claim 14 wherein said drive means arecomprised of solenoid coils driving a movable armature and each of saidhammers is coupled to the associated one of said drive means by a drivermember extending therebetween wherein the driver members associated withthose of the drive means which are separated from the associated hammerby an intervening one of the other drive means have an angledconfiguration and extend around said intervening drive means. 16.Printout mechanism operating from coded input signals which identifyspecific ones of a plurality of distinct characters to be printed,comprising: a fixed array of stationary character-defining elementsarranged in a plurality of rows and columns with at least one elementdefining each of said distinct characters being in each of said columnsin at least one of the rows transected thereby, each of saidcharacter-defining elements having a projecting portion shaped inconformity with the character defined thereby, drive means for travelinga recording web past said array of character-defining elements along apath at which said recording web is parallel to said array and moves ina direction parallel to the columns of character-defining elements, anda plurality of actuator elements disposed in a matching array of rowsand columns on the opposite side of the path of travel of said recordingweb from said array of character-defining elements, each of saidactuator elements having a flat-headed movable hammer and a separatelyenergizable electrical drive means therefor for imPressing saidrecording web against the projecting portion of the associatedcharacter-defining element, wherein said electrical drive means of eachof said actuators has a greater extent along said rows than theassociated hammer and wherein said array of character-defining elementshas a plurality of rows of like character-defining elements with eachsuccessive row thereof being offset from the adjacent rows in adirection transverse to the travel of said recording web and with thecharacter-defining elements of each such row being spaced apart by aplurality of column spaces, said electrical drive means of saidactuators for each distinct character being correspondingly arranged ina plurality of rows, whereby said electrical drive means of saidactuators may be equidistantly spaced from said array ofcharacter-defining elements.
 17. Printout mechanism operating from codedinput signals which identify specific ones of a plurality of distinctcharacters to be printed, comprising: a fixed array of stationarycharacter-defining elements arranged in a plurality of rows and columnswith a plurality of elements corresponding to each distinct character ineach column, each of said character-defining elements having aprojecting portion shaped in conformity with the character definedthereby, drive means for traveling a recording web past said array ofcharacter-defining elements along a path at which said recording web isparallel to said array and moves in a direction parallel to the columnsof character-defining elements, and a plurality of actuator elementsdisposed in a matching array of rows and columns on the opposite side ofthe path of travel of said recording web from said array ofcharacter-defining elements, each of said actuator elements having aflat-headed movable hammer and a separately energizable electrical drivemeans therefor for impressing said recording web against the projectingportion of the associated character-defining element, each of theplurality of similar character-defining elements in the same columnhaving a separate one of said actuators associated therewith, andcontrol means sequentially utilizing different ones of the plurality ofsimilar character-defining elements in the same column to imprintsuccessive ones of the same character in successive lines on saidrecording web whereby the printing speed of said printout mechanism isnot limited by the operation time of a single actuator.
 18. Printoutmechanism operating from coded input signals which identify specificones of a plurality of distinct characters to be printed, comprising: afixed array of stationary character-defining elements arranged in aplurality of rows and columns with at least one element defining each ofsaid distinct characters being in each of said columns in at least oneof the rows transected thereby, each of said character-defining elementshaving a projecting portion shaped in conformity with the characterdefined thereby, drive means for traveling a recording web past saidarray of character-defining elements along a path at which saidrecording web is parallel to said array and moves in a directionparallel to the columns of character-defining elements, and a pluralityof actuator elements disposed in a matching array of rows and columns onthe opposite side of the path of travel of said recording web from saidarray of character-defining elements, each of said actuator elementshaving a movable hammer with a flat head formed of resilient materialand a separately energizable electrical drive means therefore forimpressing said recording web against the projecting portion of theassociated character-defining element.
 19. Printout mechanism operatingfrom coded input signals which identify specific ones of a plurality ofdistinct characters to be printed, comprising: a fixed array ofstationary character-defining elements arranged in a plurality of rowsand columns with at least one element defining each oF said distinctcharacters being in each of said columns in at least one of the rowstransected thereby, each of said character-defining elements having aprojecting portion shaped in conformity with the character definedthereby, drive means for traveling a recording web past said array ofcharacter-defining elements along a path at which said recording web isparallel to said array and moves in a direction parallel to the columnsof character-defining elements, and a plurality of actuator elementsdisposed in a matching array of rows and columns on the opposite side ofthe path of travel of said recording web from said array ofcharacter-defining elements, each of said actuator elements having aflat-headed movable hammer and a separately energizable electrical drivemeans therefor for impressing said recording web against the projectingportion of the associated character-defining element, wherein saidflat-headed hammers have a rounded edge transverse to the direction ofpaper movement.
 20. A printout device for printing from coded signalsthat identify specific ones of a plurality of distinct characters to beprinted, comprising: an array of electrostatic imprinting means arrangedin a plurality of rows and columns, each such imprinting means having acharacter-defining portion shaped in conformity with one of saiddistinct characters and wherein each column includes at least oneimprinting means corresponding to each of said distinct characters,means for moving a recording web along said array of electrostaticimprinting means, in a direction parallel to said columns thereof, saidrecording web being capable of retaining an electrical charge for atleast a limited period, an array of actuators each being connected to aseparate one of said imprinting means for transmitting a pulsedelectrical voltage thereto to cause said imprinting means to impart acharge to said recording web wherein the charged area of said web has aconfiguration conforming to the character defined by said means, saidactuators of any row being energizable independently of the timing ofenergization of the actuators of other rows, a data storage receivingand temporarily storing said coded signals, and control means forrepetitively examining said data storage to detect coincidences betweenthe momentary position of an area of said recording web and animprinting means corresponding to a character which is to be imprintedthereat, said control means energizing the corresponding ones of saidactuators upon detection of said coincidences, and wherein said controlmeans cyclically repeats said examination of said data storage andenergization of appropriate ones of said actuators more than once whilea given line of printing on said recording web moves from a given row ofsaid imprinting means to the adjacent row thereof.
 21. A printout deviceas defined in claim 19 wherein said character-defining elements of saidimprinting means are fixed with respect to each other and situated at aflat planar surface along which said recording web travels.
 22. Aprintout device as defined in claim 21 further comprising a conductivebacking electrode spaced from said character-defining elements of saidimprinting means to define a passage for said recording web.
 23. Aprintout device as defined in claim 22 wherein said backing electrodehas a plurality of apertures therethrough, and further comprising vacuummeans coupled to said apertures for holding said recording webthereagainst.
 24. A printout device as defined in claim 19 wherein saidarray of imprinting means are at least partially imbedded in aninsulative matrix member whereby said imprinting means may be removedand replaced as a unit.
 25. A printout device as defined in claim 24wherein said imprinting means extend at least to the surface of saidmatrix member opposite from said character-defining elements and furthercomprising a unitized connector board fittable against said surface andremovable tHerefrom and carrying an array of electrical connectors eachpositioned to connect with a separate one of said imprinting means whensaid board is implaced against said matrix member.